1. Field of the Invention
A process is described for making glyoxylate hemiacetals from carbon monoxide under pressure with an alcohol or a formate ester. Since methods for converting glyoxylate hemiacetals to the free glyoxylates are known to those skilled in the art, this invention also relates in principle to a novel method for preparing glyoxylates.
2. Description of the Prior Art
There is much literature on the synthesis of glyoxylic acid, its esters and acetals. They have been made from two-carbon atom organic compounds like C.sub.2 H.sub.5 OH, CH.sub.3 COOH, Br.sub.2 CHCOOH, (CHO).sub.2, and HOCH.sub.2 COOH; from three-carbon compounds like glycerine; from four-carbon compounds like ##STR2## and tartaric acid.
The literature on the preparation of formate esters from alkali metal alkoxides and CO is also extensive; however, no formation of glyoxylate is reported, and an experiment done by us under similar conditions yielded no glyoxylate.
Formate ester has been deprotonated presumably to (COOR).sup.- [G. K. Koch et al., Tetrahedron Letters, (7), 603, 1974]; and, the formation of any glyoxylate is not reported and was not observed by us under analogous conditions. Likewise, J. C. Powers et al., Tetrahedron Letters, (22) 1713 (1965) observed deprotonation of HCOOR but failed to obtain reactions of (COOR).sup.- with electrophiles.